Bonus et quietus et bonus.

Finally, what is more appropriate for a good man, a good and quiet citizen, than to absent himself from civil quarrels?

Caesar is trying to convince Cicero here not to get involved in some affair or other, in what Cicero describes as a nasty letter (odiosae litterae).

I don’t really like the repetition of “good … good” here, but it’s there to match the original bono … bono. Though looking at it now I see there’s a rather handsome sort of antimetabolic chiasmus in viro bono et quieto et bono civi that I hadn’t seen before. Not sure how I could render that in English.

Given the context I translated abesse as “to absent oneself from” rather than “to be absent from”. This may or may not be entirely justified.